Apparatus for stitching bag material



0a. 25, 1932. K; MMER 1,884,032

APPARATUS FOR STT'ICHING BAG MATERIAL Filed July 2. 1928- '5 Sheets-Sheet 1 invader Oct. 25, 1932. ME 1,884,032

APPARATUS FOR STITCHING BAG IATFRIAL Filed July 2, 1928 s Sheets-She et 2 AM I 0a. 25, 1932. K. Man 1, 8 0 2 APPARATUS FOR STITCHINGBAG MATERIAL Filed July 2, 1928 3 Sheets-Sheet 3 'fully disclosed.

Patented Oct. 25, 1932 "UNITED STATES PATENT OFFICE KARL MAIER, 0F ST'U'T'I'GART, GERMANY, ASSIGQTOR TC "UN ION SPECIAL MASCHINEItr FABRIK G. I. B. 3., OF STUTTGART, GERMANY APPARATUS ron srrrcnrne BAG MATERIAL Application filed July 2, 1828, serial No. 289,787, and in Germany October 11, 1927.

The invention relates to new and useful improvements in an apparatus for. stitching bag material, and more particularly to an apparatus for simultaneously stitching the side edge portions of the bag material.

An object of the invention is to provide an apparatus of the above type having independent stitching units for stitching the side edge portions of the bag material with independent feeding mechanisms, each of which includes a puller for insuring a uniform feed of the material and the proper placing of the lines of stitching relative to the edges of the material.

A further object of the invention is to provide an apparatus of the above type wherein the stitching and feeding units may be adusted relative to each other for d'iiferent widths of bag material.

A further object of the invention is to provide an apparatus of the above type with means disposed between the stitching units forsupporting and feeding the bag material which supporting mea as is operated in unison with the feeding units.

A'further object of the invention isto provide an apparatus of the above type wherein the means located between the stitching units for feeding the bag material is of an endless type and is provided with means for placing the blanks of bag material being-stitched so as to insure that the stitching units Will begin simultaneously the operation ppon the A further object of the invention is to provide an apparatus of the above c with independent cutting devices located in rear of the pullers and operated automatically by a pattern mechanism traveling in unison with the feed of the bag blank whereby the actuation of the cutters will be effected in the interval between the bag blanks passing the cutters.

These and other objects will in part be obvious and will in part be hereinafter more In the drawings Fig. 1 1s a view partly in front elevation and partly in section showing an apparatus embodying the invention.

v Fig. 2 is'a plan view of the apparatus, certain of the parts being in section.

Fig. 3 is an end view of one of the stitching units and one of the puller units, also showing the cutter associated therewith, the view being taken on theline AA of Fig. 1. i

Fig. 4 is a view in elevation on the line 13-13 of Fig. 3 with the puller rollers omitted.

Fig. 5 is a view showing in side elevation a portion of the cutter operating lever, the pattern cam mechanism for actuating the lever, and the support therefor, the view being takenin the direction of the arrow 0 ofFig. 1.

Fig. 6 is a diagrammatic view showing the relative position of the stitching mechanism, the puller and the cutters, and the passing bag blanks.

Fig. 7 is a diagrammatic view showing in plan a modified form of conveyor between the stitching units and the location of the Same relative to the stitching units. n

Fig. 8 is a longitudinal sectionalview through a portion of the conveyor.

The invention is directed'to an apparatus for stitching bag material, and more particularly to an apparatus for stitching blanks of bag material for forming bags. Two stitching units are used, which are pref,- erably right and left hand units so that lines of stitching may be simultaneously formed at the opposite side edge portions of the bag blank. These stitching units are independent of each other, but driven from the same actuating shaft. Associated directly with each stitching unit is a four-motion feed 8 and associated with each stitching unit is a puller feed which includes puller rollers and located directly in rear of the needle and engaging the stitched edge portion of the bank for pulling the same through the appastitching units is an endless conveyor for con- Y veying the blanks. The endless conveyor is provided with means for placing the blanks so that the edge portion extending across the gongeyor is at right angles to the line of The apparatus also includes a pattern mechanism in the form of a traveling chain having a cam link thereon which engages a lever for actuating the cutter. There is a pattern chain for each cutter and these chains are so timed as to actuate the cutter positively to cut the enchained loops at the interval between when the bag blanks are passing the cutters.

Referring more in detail to the drawings: The apparatus embodying the invention includes a supporting table 1 on which is mounted a sewing machine 2 having a stitching unit which includes a needle bar-3 and a needle 4. The needle bar is reciprocated by the usual needle lever which is operated by 'an eccentric on the main actuatingshaft of the sewing machine. The main actuating shaft is provided with a gear 5. Located in suitable earings in the table is a main actuating shaft 6 which is provided with a belt wheel 7 driven by a belt 8 from a suitable power mechanism. This actuating shaft 6 is provided with gears 9, 9 which are adapted to mesh with the gears 5, 5 respectively of the sewing units. Thus it is that the sewing units are driven in the same timing. The material is held on the work support by a presser foot 10 of the usual construction and the material is fed beneath the presser foot by means of a four-motion feeding mechanlsm including a feed dog 11.

These feeding mechanisms are independent of each other but are driven from the actuating shaft of the sewing machines that the four-motion feeding mechanisms of both units operate in unison for feeding the material beneath the presser foot.

Associated with each sewing machine is a puller feed unit 12. This puller feed unit includes an upper puller roller 13 and a lower puller roller 14. The lower puller roller 14 is mounted on a shaft 15 and the shaft 15 is driven by suitable connections 15 from the main shaft of the sewing machine as is usual with puller units. See for example, U. S. Patent No. 1,145,619, granted D. S. Seymour, July, 1915. The rollers 13 and 14 are shaped so as to intermesh-and one drives the other. These rollers as clearly shown in the drawings are located directly in rear of the presser foot 10 and operate upon the edge portion of the bag material.

Located between the sewing machines and the puller units is an endless conveyor 16.

This endless conveyor 16 passes about rollers 17 and 18 carried by the shafts 19 and 20, respectively. The shaft 19 is provided with a sprocket 21 over which a sprocket chain 22 runs. This sprocket chain also runs over a sprocket wheel of the main shaft of the puller unit. The puller unit shaft is, of course, intermittently operated so that the uller rollers are intermittently turned to eed the material a distance corresponding to the feed stroke of the four-motion feed dogs. The shaft 19 is given an intermittent step movement which is timed to correspond to the step movement of the puller rollers and is also given the same extent of movement as the puller rollers so that the material restin on the endless conveyor 16 will be conveyed to the sewing units and through the sewing units and pullers at the same rate of feed as that imparted to the material by the feed dogs and puller units. The shaft 20 is driven by a. sprocket chain running over sprocket wheels on the shafts 19 and 20.

This endless conveyor 16 as shown in Fig.

2 of the drawings is provided with indicating devices 23, 23. These indicating devices aid in the placing of the blanks in the conveyor so that the edge portion extending from one sewing unit to the other is at right angles to the path of travel of the conveyor and the line of feed. The blank is positioned on-the conveyor by guides 24, 24 whichare adjustably attached to the bed plate of the sewing machine. A bag blank to be stitched is indicated at 25 in the drawings.- The-direction of feed is indicated by the arrow D in the drawings. The side edge portion 26 of the blank 25 is directed to the right hand stitching unit while the side edge portion 27 oftheblankis directed to the left hand stithing unit. The lines of stitches formed by the stitching units are indicated at 28, 28. The

blanks are placed on the endless conveyor between the guides,24, 24 with the advance edge portion properly placed relative to the indicating devices 23. This insures that the blank will be delivered to the needles of the stitching units simultaneously so that the stitching of the blank and feeding of the blank by the stitching and feeding units will begin simultaneously. This insures an even travel of the bag blank and the positioning of the lines of stitches at a uniform distance from the edge of the blank throughout the entire width thereof.

In Figs. 7 and 8 of the drawings I have shown a modified form of endless conveyor. In this form of the conveyor there are two chains 29, 29. Certain of the links are provided with lugs 30 and with cross bars 31, extending from one chain to the other. Associated with certain of these cross bars are placing guides 32. The placing guides 32 are attached to the lugs 30 so that they may be adjusted in a direction lengthwise of the conveyor. The bag blank is placed on this endless conveyor b the placing guides 32, 32 as shown in Figs. and 8. These placing guides not only insure that the blanks shall be properly started, but also insure that the blanks shall be placed in a certain region on the conveyor.

The puller unit is attached to the sewing machine. As shown in Fig. 2 both the puller unit and the sewing machine are mounted on the supporting table so that they ma be adjusted toward and from each other. fl) order to accomplish this a threaded shaft 33 is provided which may be turned b a suitable crank 34.. This shaft has both right and left hand threads and when turned in one direction it will move thesewing units and puller units toward each other and when turned in the opposite direction it will move the sewing units away from each other. The gear wheel 9 and the sprocket chain and wheel 21 over.

which it runs are adjusted by hand to accord with the adjustments of the machine. By

changing the conveyor between the units,

when found necessary, the apparatus is capable of a wide range of adjustment so that blanks of different widths may be stitched.

Associated with each puller unit is a cutting unit which includes an upper movable cutting knife and a lower fixed cutting.

knife 36. The knife 35 is carried by a rod 3 mounted for reciprocation in the bearings 38 of the puller unit. The movable cutter has an inclined shear cutting edge with a guide finger which overlies the stationary cutting member and guides the cutter in its movements. The rod 37 carrying the movable cutter is connected by a'lfnk 39 with a lever 40. There is, of course, a lever 40 associated with each cutting unit. The lever 40 is actuated by a pattern mechanism. This pattern mechanism consists of a chain 41 running over a sprocket wheel 42 carried by the shaft 15 on which the lower puller roller is mounted. The chain also runs over a sprocket wheel 43 mounted for vertical adjustment on a depending bracket 44. This is for the purpose ofenabling the chain to be lengthened or shortened by adding to or taking away links. One or more of the links are provided with an actuating cam 45. When this cam 45 passes beneath the end of the lever 40 the leyer will be raised and thFs will force the movable cutting blade downward so as to cause the cutters to sever whatever may be placed by the cutters. The purpose of the pattern cams for actuating the cutters is to bring about anactuation of the cutters'only at the interval when the chain connectingthe stitched blanks is between the cutters orthe chain and the protecting strip, if one is used. In Fig. 4 ofthe drawings there is shown a protecting strip 46 which is folded about the edges of the blank and the stitches are passed through this strip for securing the edges. The strip is of a length so as to pass from one blank to the other. i

When the cam passes from beneath the end of the lever the lever is suflicientl as to drop and raise the cutter. his lifting of the cutter may be accomplished in other ways.

The operation of the apparatus will be apweighted n sewing units will insure that the side edge portions are properly directed to the needles. As soon as the blank passes beneath the presser foot and into range of the puller rollers the puller rollers will pull on the side edge portions only of the blank and these puller rollers may be timed so as to insure that the blanks will be evenly fed and directed so as to properly position the line of stitches relative to the edges of the blank. After the blank passes from the uller rollers the conveyor will carry the blank along and the stitched blank may be held spaced from the next blank which is coming through the apparatus. A connecting line of enchained thread loops is formed between the stitched blanks. At the proper time the pattern chains operate the lever controlling the cutters for causing the cutters to sever the enchained thread loops between the stitched blanks. When the blank is placed on the endless conveyor it is located in a predetermined position thereon by the placing means associated .with the endless conveyor. The front edge the cam links will always operate the cutters so as to cut the enchained thread loops between stitchedblanks.

It is obvious that minor changes in the details of construction and the arrangement of parts may be made without departing from the spirit of the invention as set forth in the appended cliims.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent, is 1 1. An apparatus for seiving bag blanks comprising sewing machines for simultaneously stitching the opposite edge portions of the blanks, an intermittently operated puller unit associated with each sewing machine and o crating to insure an even feed of both e ge portions of the blank and a uniform placing of the stitches relative to the edges thereof, and an intermittently operated conveyor located between said machines for feeding the blanks to the sewing machines and away from the puller units, said conveyor having means thereon to aid in the positioning of the blanks thereon so as to be properly presented to the sewing machines. 2. An apparatus for sewing bag blanks comprising sewing machines for simultaneously-stitching the opposite edge portions of the blanks, an intermittently operated puller unit associated with each sewing machine and operating to insure an even feed of both edge portions of the blank and a uniform placing of the stitches relative to the edges thereof, andan intermittently operated endless conveyor located between the sewing machines and puller units for feeding blanks to the sewing machines during sewing and away from the puller units after they are stitched, said conveyor having means thereon to aid in the positioning of the blanks thereon so as to be properly presented to the sewing machines.

3. An apparatus for sewing bag blanks comprising sewing machines for simultaneously stitching the opposite edge portions of the blanks, an intermittently operated puller unit associated with each sewing machine and operating to insure an even feed of both edge portions of the blank and a uniform placing of the stitches relative to the edges thereof, and an endless conveyor located between the sewing machines and puller units and intermittently operated by and in timing with the puller units for feeding blanks to the sewing machines during sewing and away from the puller units after they are stitched, said conveyor having means thereon to aid in the positioning of the blanks thereon so as to be properly presented to. the sewin machines.

4. Kn apparatus for sewing bag blanks comprising sewing machines for simultaneously stitching the opposite edge portions of the blanks, an intermittently operated puller unit associated with each sewing machine, a

cutter associated with each puller unit and located in rear thereof for cutting the enchained thread loops between stitched blanks, means for feeding the blanks to the sewing machineat predetermined time intervals and pattern means controlling the actuation of the cutters so that the cutters are operated at the time interval between the stitched blanks.

5. An apparatus for sewing bag blanks comprising sewing machines for simultaneously stitching the opposite edge portions of the blanks, a. puller unit associated with each sewing machine, an endless conveyor located between the sewing machines and extending from a point well in advance of the needles of the sewing machines to a point well in rear of the puller units, said conveyor having means thereon to aid in the positioning of the blanks thereon so as to be properly presented to the sewing machines.

6. An apparatus for sewing bag blanks comprising sewing machines for simultaneously stitching the opposite edge portions of the blanks, a puller unit associated with each sewing machine, an endless conveyor located between the sewing machines and eX- tending from a point well in advance of the needles, of the sewing machines to fa point well in rear of the puller units, and means for intermittently operating the puller units 'needles of the sewing machines to a point well in rear of the puller units, said conveyor having means thereon to aid in the positioning of the blanks thereon so as to be proper- 1y presented to the sewing machines,-means for intermittently operating the puller units from and in timing with the sewing machines and for intermittently operating the endless conveyor from and in timing with the puller units, a cutting device associated with each puller unit and located in rear of the rollers of the puller units, and means for actuating said cutters so as to cut the enchained thread loops between stitched blanks.

8. An apparatus for sewing bag blanks comprising sewing machines for simultaneously stitching the opposite edge portions of the blanks, a puller unit associated with each sewing machine, an endless conveyor located between the sewing machines and extending from a point well in advance of the needles of the sewing machines .to a point well in rear of the puller units, means for intermittently operating the puller units from and in timing with the sewing machines, and for intermittently operating the endless conveyor from and in timing with the puller units, said conveyor having means thereon to aid in the positioning of the blanks thereon so as to be properly presented to the sewing machines, a cutting device associated with each puller unit and located in rear of the rollers of the puller units, means for actuating said cutters so as to cut the enchained thread loops between stitched blanks, and devices for placing the blanks on the endless conveyor in a predetermined position relative to the timing of the cutters.

In testimony whereof, I aflix my signature.

KARL MAIER. 

